Coronary microvascular dysfunction: prevalence and aetiology in patients with suspected myocardial ischaemia

AIM

To evaluate the prevalence, aetiology, and corresponding morbidity of coronary microvascular dysfunction (CMD) in patients with suspected myocardial ischaemia.

MATERIALS AND METHODS

The present study included 115 patients with suspected myocardial ischaemia who underwent stress perfusion cardiac magnetic resonance imaging. CMD was assessed visually based on the myocardial perfusion results. The CMR-derived myocardial perfusion reserve index (MPRI) and left ventricular (LV) strain parameters obtained using the post-processing software CVI42 were employed to evaluate LV myocardial perfusion and deformation. LV strain parameters included global longitudinal, circumferential, and radial strain (GLS, GCS, and GRS), global systolic/diastolic longitudinal, circumferential, and radial strain rates (SLSR, SCSR, SRSR, DLSR, DCSR, and DRSR).

RESULTS

Of the 115 patients, 12 patients were excluded and 103 patients were finally included in the study. CMD was observed in 79 % (81 patients, aged 53 ± 12 years) of patients. Regarding aetiology, 91 (88 %) patients had non-obstructive coronary artery disease (CAD), eight (8 %) had obstructive CAD, and four (4 %) had hypertrophic cardiomyopathy (HCM). The incidence of CMD was highest (100 %) in patients with HCM, followed by those with non-obstructive CAD (up to 79 %). There were no statistical differences between CMD and non-CMD groups in GCS, GRS, GLS, SRSR, SCSR, SLSR, DCSR, DRSR and DLSR.

CONCLUSION

The incidence of CMD was higher in patients with signs and symptoms of ischaemia. CMD occurred with non-obstructive CAD, obstructive CAD, and HCM, with the highest prevalence of CMD in HCM.

The influence of COMT and ABCB1 gene polymorphisms on sufentanil analgesic effect for postoperative pain in children with fracture

The aim of this observational study was to investigate the effects of catechol-O-methyltransferase (COMT) and ATP-binding cassette transporter B1 (ABCB1) gene polymorphisms on the postoperative analgesic effect of sufentanil in Chinese Han pediatric patients with fractures. A total of 185 pediatric patients who underwent fracture surgery were included. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the polymorphisms of COMT and ABCB1 genes. Sufentanil was used for postoperative analgesia. The pain level of the patients was evaluated using the face, legs, activity, cry, and consolability scale before surgery, during awakening, at 2, 6, 12, and 24 hours after surgery. The postoperative Ramsay sedation score, sufentanil consumption, and incidence of adverse reactions were also recorded. Pediatric patients with different genotypes of ABCB1 and COMT showed no statistically significant differences in general data such as age, gender, weight, height, surgical duration, and American Society of Anesthesiologists classification (P > .05). There were no statistically significant differences in sedation scores after surgery between different genotypes of ABCB1 and COMT (P > .05). Among patients with CC genotype in ABCB1, the pain scores and total consumption of sufentanil at awakening, 2 and 6 hours after surgery were higher compared to TT and CT genotypes (P < .05), while there were no statistically significant differences between TT and CT genotypes (P > .05). Among patients with AA genotype in COMT, the pain scores and total consumption of sufentanil at awakening, 2, 6, 12, and 24 hours after surgery were higher compared to AG and GG genotypes (P < .05), while there were no statistically significant differences between AG and GG genotypes (P > .05). There were no statistically significant differences in adverse reactions between different genotypes of ABCB1 and COMT (P > .05). The polymorphisms of COMT gene rs4680 and ABCB1 gene rs1045642 are associated with the analgesic effect and consumption of sufentanil in pediatric patients after fracture surgery.

Mineralocorticoid promotes intestinal inflammation through receptor dependent IL17 production in ILC3s

Aldosterone is a key mineralocorticoid involved in regulating the concentration of blood electrolytes and physiological volume balance. Activation of mineralocorticoid receptor (MR) has been recently reported to participate in adaptive and innate immune responses under inflammation. Here, we evaluated the role of aldosterone and MR in inflammation bowel diseases (IBD). Aldosterone elevated in the colon of DSS-induced colitis mice. Aldosterone addition induced IL17 production and ROS/RNS level in group 3 innate lymphoid cells (ILC3s) and exacerbated intestinal injury. A selective mineralocorticoid receptor antagonism, eplerenone, inhibited IL17-producing ILC3s and its ROS/RNS production, protected mice from DSS-induced colitis. Mice lacking Nr3c2 (MR coding gene) in ILC3s exhibited decreased IL17 and ROS/RNS production, which alleviated colitis and colitis-associated colorectal cancer (CAC). Further experiments revealed that MR could directly bind to IL17A promoter and facilitate its transcription, which could be enhanced by aldosterone. Thus, our findings demonstrated the critical role of aldosterone-MR-IL17 signaling in ILC3s and gut homeostasis, indicating the therapeutic strategy of eplerenone in IBD clinical trial.

Relationship between coronary microvascular dysfunction (CMD) and left ventricular diastolic function in patients with symptoms of myocardial ischemia with non-obstructive coronary artery disease (INOCA) by cardiovascular magnetic resonance feature-tracking

AIM

To investigate whether there was an association between coronary microvascular dysfunction (CMD) and left ventricular (LV) diastolic function in patients with myocardial ischemia with non-obstructive coronary artery disease (INOCA).

MATERIALS AND METHODS

Our study included 115 subjects with suspected myocardial ischemia that underwent stress perfusion cardiac magnetic resonance (CMR). They were divided into non-CMD and CMD two groups. CMR-derived volume-time curves and CMR-FT parameters were used to assess LV diastolic function using CVI42 software. The latter included global/regional LV peak longitudinal, circumferential, radial diastolic strain rate (LDSR, CDSR, RDSR). Logistic regression analysis was performed with CMR-FT strain parameters as independent variables and CMD as dependent variables, and the effect value was expressed as an odds ratio (OR).

RESULTS

Of the 115 patients, we excluded data from 23 patients and 92 patients (56.5% male；52 ± 12 years) were finally included in the study. Of these, 19 patients were included in the non-CMD group (49 ± 11 years) and CMD group included 73patient (52 ± 12 years). The regional CDSR (P=0.019), and regional RDSR (P=0.006) were significantly lower in the CMD group than in non-CMD group. But, regional LDSR in CMD group was higher than non-CMD (P=0.003). In logistic regression analysis, regional LDSR (adjusted β= 0.1, 95%CI 0.077, 0.349, p=0.002) and RDSR (adjusted β= 0.1, 95 % CI 0.066, 0.356, p=0.004) were related to CMD.

CONCLUSIONS

LV myocardial perfusion parameter MPRI was negatively correlated with LV diastolic function (CDSR) which needs to take into account the degree of diastolic dysfunction.

Quercitrin attenuates the progression of osteoarthritis via inhibiting NF-κB signaling pathways and enhance glucose transport capacity

Osteoarthritis (OA) is a common musculoskeletal disorder that impairs function and reduces the quality of life. Extracellular matrix (ECM) degradation and inflammatory mechanisms are crucial to the progression of OA. In this study, we aimed to investigate the anti-inflammatory activity, anti-ECM degradation property, and glucose transport capacity of quercitrin (QCT) on IL-1β-treated rat primary chondrocytes. Rat primary chondrocytes were treated with IL-1β to simulate inflammatory environmental conditions and OA in vitro. We examined the effects of QCT at concentrations ranging from 0 to 200 μM on the viability of rat chondrocytes and selected 5 μM for further study. Using qRT-PCR, immunofluorescent, immunocytochemistry, and western blotting techniques, we identified the potential molecular mechanisms and signaling pathways that are responsible for these effects. We established an OA rat model through anterior cruciate ligament transection (ACLT). The animals were then periodically injected with QCT into the knee articular cavity. Our in vivo and in vitro study showed that QCT could inhibit IL-1β-activated inflammation and ECM degradation in chondrocyte. Furthermore, QCT could inhibit the NF-κB signal pathway and enhance glucose transport capacity in the IL-1β-stimulated chondrocytes. In vivo study proved that QCT attenuates OA progression in rats. Overall, QCT inhibited the activation of NF-κB and enhanced glucose transport capacity to alleviate the progression of OA.

"Triple-low" radiation dose bronchial artery CT angiography before bronchial artery embolisation: a feasibility study

AIM

To explore the feasibility of a "triple-low" dose (low tube voltage, low tube current, and low contrast agent volume) bronchial artery computed tomography (CT) angiography (CTA) to replace routine dose bronchial artery CTA before bronchial artery embolisation (BAE).

MATERIALS AND METHODS

CTA was obtained from 60 patients with body mass index (BMI) < 30 kg/m2 using a 256 multi-section iCT system, and they were divided into two groups: (1) group A: 100 kVp, 100 mAs, 50 ml contrast medium (CM); (2) group B: 120 kVp, automatic tube current modulation (ACTM), 80 ml CM. CT attenuation of the thoracic aorta, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated, and subjective image quality scores and traceability scores assessed. The effective radiation dose was calculated.

RESULTS

The radiation dose was reduced by 79.7% in group A compared to group B (p<0.05). The CT attenuation of the thoracic aorta was increased by approximately 13% in group A compared to group B (p<0.05). Higher image noise, lower SNR, and CNR were obtained in group A compared to group B (all p<0.05). Both subjective image quality scores and traceability scores did not differ between groups A and B (both p>0.05).

CONCLUSION

It is feasible to use the "triple-low" dose CTA protocol for patients with a body mass index (BMI) < 30 kg/m2. The radiation dose was reduced by 79.7%, and the dose of contrast medium was reduced by 37.5% to ensure the diagnostic value.

The Value of Progression-Free Survival at Three Years as a Primary Endpoint for Studies on Radiotherapy in Patients with Locally Advanced Cervical Cancer: Individual Patient Data and Validation From 27 Randomized Trials

PURPOSE/OBJECTIVE(S)

A traditional endpoint for locally advanced cervical cancer (LACC) clinical trials is overall survival (OS) with five years of follow-up. At present, many clinical trials evaluating concurrent chemoradiotherapy combined with immunotherapy for LACC are underway in worldwide. The use of a shorter-term endpoint could significantly speed the translation of research findings into practice. The primary hypothesis was that PFS with three years of follow-up (PFS36) is an appropriate primary endpoint to replace OS with five years of follow-up (5-year OS).

MATERIALS/METHODS

The primary hypothesis was developed from our individual data, was further investigated using phase III randomized controlled trials (RCTs), and then externally validated by phase II trials and retrospective studies up to 2022. Correlation analysis at the treatment-arm level was performed between 2-, 3-, 4-, and 5-year PFS rates and 5-year OS, using the Pearson correlation coefficient r in weighted linear regression, with weight equal to patient size. The MEDLINE, Embase, and PubMed databases, together with the Cochrane Central Register of Controlled Trials, were searched from January 1, 1999, to February 2, 2023. Articles eligible for inclusion contained complete survival data.

RESULTS

A total of 613 patients with histologically confirmed, FIGO 2009 stage IB-IVA cervical cancer who underwent radiotherapy at our institute from January 2010 to December 2013 were eligible. Individual patient data were pooled to explore the correlation between PFS and the OS trend. The recurrence rates for years 1 through 5 were 12.9%, 7.3%, 3%, 2.3%, and 1.8%, respectively. The median recurrence time was 13 months and the median time from recurrence to death was 12.2 months. Within all the recurrence, 47.3% of recurrences occurred during the first year, 71.4% in the first two years, and 85% in the first three years. Patients who did not achieve PFS36 had a 5-year OS rate of 30.3%. In contrast, a 5-year OS rate of 98.2% was observed in patients who achieved PFS36. Further data were extracted from 27 RCTs on locally advanced cervical cancer. The trials included 57 arms, with a pooled sample size of 7,692 patients. Formal measures of surrogacy were satisfied. Quality control was performed, where studies with a high risk of bias were excluded. In trial-level surrogacy, PFS36 (r2, 0.778) was associated with 5-year OS. The correlation between PFS36 and OS was externally validated using independent phase II trials and retrospective data. In total, 23 studies representing 5,174 patients were included. PFS36 (r2, 0.719) was found to be associated with OS.

CONCLUSION

The patients who achieved PFS36 had excellent outcomes, whereas patients that experienced earlier progression had poor survival. A significant correlation was found between PFS36 and 5-year OS in clinical trials on patients with locally advanced cervical cancer. These results suggest that PFS36 is an appropriate endpoint for LACC clinical trials of radiotherapy-based regimens.

Self-Assemble Silk Fibroin Microcapsules for Cartilage Regeneration through Gene Delivery and Immune Regulation

Effective treatments for cartilage defects are currently lacking. Gene delivery using proper delivery systems has shown great potential in cartilage regeneration. However, the inflammatory microenvironment generated by the defected cartilage severely affects the system's delivery efficiency. Therefore, this study reports a silk fibroin microcapsule (SFM) structure based on layer-by-layer self-assembly, in which interleukin-4 (IL-4) is modified on silk by click chemistry and loaded with lysyl oxidase plasmid DNA (LOX pDNA). The silk microcapsules display good biocompatibility and the release rate of genes can be adjusted by controlling the number of self-assembled layers. Moreover, the functionalized SFMs mixed with methacrylated gelatin (GelMA) exhibit good injectability. The IL-4 on the outer layer of the SFM can regulate macrophages to polarize toward the M2 type, thereby promoting cartilage matrix repair and inhibiting inflammation. The LOX pDNA loaded inside can be effectively delivered into cells to promote extracellular matrix generation, significantly promoting cartilage regeneration. The results of this study provide a promising biomaterial for cartilage repair, and this novel silk-based microcapsule delivery system can also provide strategies for the treatment of other diseases.

Knockdown of Long Noncoding RNA CCAT2 Suppresses Malignant Phenotype in Human Laryngeal Squamous Cell Carcinoma

This study aimed to explore the biological role and mechanism underlying the effects of colon cancer-associated transcript 2 (CCAT2), a long noncoding RNA (lncRNA) in human laryngeal squamous cell carcinoma (LSCC). CCAT2 expression levels in clinical LSCC samples and TU-212 cell line were evaluated by quantitative real-time PCR. The correlation of CCAT2 expression level with clinical-pathological characteristics of patients and their prognosis was analyzed. The functional role of CCAT2 in human LSCC was assessed by Cell Counting Kit-8, Transwell assay, flow cytometric analysis, and LSCC xenograft experiment in vivo. The expression of potential targeted proteins was detected by Western blotting and immunohistochemistry. We found that expression of CCAT2 was significantly elevated in LSCC tissues and TU-212 cells (p<0.05). Survival analysis showed that LSCC patients with high expression of CCAT2 had a shorter 5-year overall survival rate than those with low expression (p<0.05). In addition, CCAT2 silencing with short hairpin RNA significantly decreased the proliferative and invasive potential of TU-212 cells (p<0.05) and promoted their apoptosis. In Nude mice, CCAT2 knockdown suppressed the growth of tumor and decreased its volume and weight in comparison with the controls (p<0.05). In TU-212 cells, CCAT2 silencing with short hairpin RNA significantly down-regulated the expression of β-catenin and CDK8 (p<0.05). Thus, knockdown of CCAT2 suppresses proliferation and invasion of the cells and inhibits Wnt/β-catenin signaling pathway in LSCC, which indicates novel therapeutic targets and prognostic indicators in patients with LSCC.

Platelet ITGA2B inhibits caspase-8 and Rip3/Mlkl-dependent platelet death though PTPN6 during sepsis

Platelets play an important role in the pathogenesis of sepsis and platelet transfusion is a therapeutic option for sepsis patients, although the exact mechanisms have not been elucidated so far. ITGA2B encodes the αIIb protein in platelets, and its upregulation in sepsis is associated with increased mortality rate. Here, we generated a Itga2b (Q887X) knockin mouse, which significantly reduced ITGA2B expression of platelet and megakaryocyte. The decrease of ITGA2B level aggravated the death of septic mice. We analyzed the transcriptomic profiles of the platelets using RNA sequencing. Our findings suggest that ITGA2B upregulates PTPN6 in megakaryocytes via the transcription factors Nfkb1 and Rel. Furthermore, PTPN6 inhibits platelet apoptosis and necroptosis during sepsis by targeting the Ripk1/Ripk3/Mlkl and caspase-8 pathways. This prevents Kupffer cells from rapidly clearing activated platelets, and eventually maintains vascular integrity during sepsis. Our findings indicate a new function of ITGA2B in the regulation of platelet death during sepsis.

Analysis of intercellular communication in the osteosarcoma microenvironment based on single cell sequencing data

Osteosarcoma (OS) is the most common primary bone cancer in children and young adults, patient survival rates have not improved in recent decades. To further understand the interrelationship between different cell types in the tumor microenvironment of osteosarcoma, we comprehensively analyzed single-cell sequencing data from six patients with untreated osteosarcoma. Nine major cell types were identified from a total of 46,046 cells based on unbiased clustering of gene expression profiles and canonical markers. Osteosarcoma from different patients display heterogeneity in cellular composition. Myeloid cells were the most commonly represented cell type, followed by osteoblastic and TILs. Copy number variation (CNV) results identified amplifications and deletions in malignant osteoblastic cells and fibroblasts. Trajectory analysis based on RNA velocity showed that osteoclasts in the OS microenvironment could be differentiated from myeloid cells. Furthermore, we explored the intercellular communications in OS microenvironment and identified multiple ligand-receptor pairs between myeloid cells, osteoblastic cells and their cells, including 21 ligand-receptor pair genes that significantly associated with survival outcomes. Importantly, we found chemotherapy may have an effect on cellular communication in the OS microenvironment by analyzing single-cell sequencing data from seven primary osteosarcoma patients who received chemotherapy. We believe these observations will improve our understanding of potential mechanisms of microenvironment contributions to OS progression and help identify potential targets for new treatment development in the future.

Single-cell RNA-seq of heart reveals intercellular communication drivers of myocardial fibrosis in diabetic cardiomyopathy

Myocardial fibrosis is the characteristic pathology of diabetes-induced cardiomyopathy. Therefore, an in-depth study of cardiac heterogeneity and cell-to-cell interactions can help elucidate the pathogenesis of diabetic myocardial fibrosis and identify treatment targets for the treatment of this disease. In this study, we investigated intercellular communication drivers of myocardial fibrosis in mouse heart with high-fat-diet (HFD)/streptozotocin (STZ)-induced diabetes at single-cell resolution. Intercellular and protein-protein interaction networks of fibroblasts and macrophages, endothelial cells, as well as fibroblasts and epicardial cells revealed critical changes in ligand-receptor interactions such as Pdgf(s)-Pdgfra and Efemp1-Egfr, which promote the development of a profibrotic microenvironment during the progression of and confirmed that the specific inhibition of the Pdgfra axis could significantly improve diabetic myocardial fibrosis. We also identified phenotypically distinct Hrc^hi and Postn^hi fibroblast subpopulations associated with pathological extracellular matrix remodeling, of which the Hrc^hi fibroblasts were found to be the most profibrogenic under diabetic conditions. Finally, we validated the role of the Itgb1 hub gene mediated intercellular communication drivers of diabetic myocardial fibrosis in Hrc^hi fibroblasts, and confirmed the results through AAV9-mediated Itgb1 knockdown in the heart of diabetic mice. In summary, cardiac cell mapping provides novel insights into intercellular communication drivers involved in pathological extracellular matrix remodeling during diabetic myocardial fibrosis.

Gardenoside ameliorates inflammation and inhibits ECM degradation in IL-1β-treated rat chondrocytes via suppressing NF-κB signaling pathways

Osteoarthritis (OA) places a significant burden on society and finance, and there is presently no effective treatment beside late replacement surgery and symptomatic relief. The therapy of OA requires additional research. Gardenoside is a naturally compound extracted from Gardenia jasminoides Ellis, which has a variety of anti-inflammatory effects. However, few studies have been conducted to determine the role of gardenoside in OA. This study aimed to explore whether gardenoside has effect in OA treatment. Rat primary chondrocytes were treated with IL-1β to simulate inflammatory environmental conditions and OA in vitro. We examined the effects of gardenoside at concentrations ranging from 0 to 200 μM on the viability of rat chondrocytes and selected 10 μM for further study. Via in vitro experiments, our study found that gardenoside lowers the gene expression of COX-2, iNOS, IL-6, and reduced the ROS production of chondrocytes induced by IL-1β. Moreover, it effectively alleviates ECM degradation caused by IL-1β and promotes the ECM synthesis in chondrocytes by upregulating collagen-II and the ACAN expression, downregulating the expression of MMP-3, MMP-13, and ADAMTS-5 expression. Further, our study showed that gardenoside inhibits NF-κB signaling pathway activated by IL-1β in chondrocytes. We established an OA rat model by anterior cruciate ligament transection (ACLT). The animals were then periodically injected with gardenoside into the knee articular cavity. In vivo study suggested that gardenoside attenuates OA progression in rats. As a whole, in vitro and in vivo results highlight gardenoside is a promising OA treatment agent.

Madecassic Acid Ameliorates the Progression of Osteoarthritis: An in vitro and in vivo Study

PURPOSE

Osteoarthritis (OA) places a significant burden on society and finance, and there is presently no effective treatment besides late replacement surgery and symptomatic relief. The therapy of OA requires additional research. Madecassic acid (MA) is the first native triterpenoid compound extracted from Centella asiatica, which has a variety of anti-inflammatory effects. However, the role of MA in OA therapy has not been reported. This study aimed to explore whether MA could suppress the inflammatory response, preserve and restore chondrocyte functions, and ameliorate the progression of OA in vitro and in vivo.

METHODS

Rat primary chondrocytes were treated with IL-1β to simulate inflammatory environmental conditions and OA in vitro. We examined the effects of MA at concentrations ranging from 0 to 200 µM on the viability of rat chondrocytes and selected 10 µM for further study. Using qRT-PCR, immunofluorescent, immunocytochemistry, and Western blotting techniques, we identified the potential molecular mechanisms and signaling pathways that are responsible for these effects. We established an OA rat model by anterior cruciate ligament transection (ACLT). The animals were then periodically injected with MA into the knee articular cavity.

RESULTS

We found that MA could down-regulate the IL-1β-induced up-regulation of COX-2, iNOS and IL-6 and restore the cytoskeletal integrity of chondrocytes treated with IL-1β. Moreover, MA protects chondrocytes from IL-1β-induced ECM degradation by upregulating ECM synthesis related protein expression, including collagen-II and ACAN, and further down-regulating ECM catabolic related protein expression, including MMP-3 and MMP-13. Furthermore, we found that NF-κB/IκBα and PI3K/AKT signaling pathways were involved in the regulatory effects of MA on the inflammation inhibition and promotion of ECM anabolism on IL-1β-induced chondrocytes.

CONCLUSION

These findings suggest that MA appears to be a potentially small molecular drug for rat OA.

Tumor Necrosis Factor-Alpha Disrupts Cx43-Mediated Corneal Endothelial Gap Junction Intercellular Communication

Connexin43 (Cx43)-mediated gap junctions are vital in maintaining corneal endothelium homeostasis. Tumor necrosis factor-alpha (TNF-α) is among the most important inflammatory factors which cause corneal endothelial dysfunction in various eye diseases. However, the effect of TNF-α on Cx43-mediated gap junctions of the corneal endothelium remains undefined. In the current research, we determined the effect of TNF-α on gap junction intercellular communication (GJIC) in rabbit corneal endothelium. To evaluate alterations of GJIC, if any, we treated ex vivo cultured rabbit corneal endothelium with different concentrations of TNF-α (2-20 ng/ml). The localization of Cx43 was analyzed by immunostaining, while RT-qPCR and western blot were used to profile the expression of Cx43 and zonula occludens-1 (ZO-1). The association between ZO-1 and Cx43 was evaluated using immunoprecipitation and double staining. GJIC activity was determined by the scrap loading and dye transfer assay (SLDT). Our data demonstrated that a high concentration of TNF-α (10 ng/ml and 20 ng/ml) disrupts the Cx43 mediated gap junction distribution in rabbit corneal endothelium and suppresses the expression of Cx43 protein. Furthermore, rabbit corneal endothelial GJIC was inhibited due to the decreased association between the ZO-1 and Cx43 proteins. Current results demonstrate that TNF-α inhibits corneal endothelial GJIC via decreasing the association between ZO-1 and Cx43, disrupting the distribution of Cx43, and downregulating the expression of Cx43 protein. This study offers a new theoretical foundation for diagnosing and treating corneal endothelial cell decompensation induced by elevated TNF-α in various eye diseases.

Glaucocalyxin a protect liver function via inhibiting platelet over-activation during sepsis

BACKGROUND

Rabdosia japonica (Burm. f.) var. glaucocalyx (Maxim.) is a perennial herb, and is traditionally used as folk medicine for treating inflammatory diseases and cancer. Gaucocalyxin A (GLA) is an ent‑kaurane diterpenoid that is isolated from the aerial parts of R. japonica (Burm. f.) var. glaucocalyx (Maxim.). In a recent study, we found that GLA protects against acute liver dysfunction induced by Escherichia coli, which is likely related to its anti-inflammatory effects. However, the mechanism by which GLA protects liver injury during sepsis is unknown.

AIM

To evaluate the anti-inflammatory function of GLA and its regulatory effect on platelet function.

METHOD

An in vivo model of sepsis was established by inoculating mice with E. coli. Live function and platelet activation were evaluated through standard assays. The levels of pro-inflammatory factors were measured through ELISA and qRT-PCR.

RESULTS

GLA alleviated liver dysfunction in the mouse model of sepsis. GLA-treated mice displayed lower complement activation and liver dysfunction after E. coli infection. GLA alleviated the decrease in peripheral platelet counts by inhibiting their clearance by Kupffer cells in liver. Furthermore, GLA inhibited platelet activation through the RIP1/RIP3/AKT pathway and downregulated C3aR expression on the platelets, thereby inhibiting liver injury and dysfunction due to excessive complement activation.

CONCLUSION

GLA can inhibit platelet activation by reducing surface expression of C3aR, which protect the liver from injury induced by excessive complement activation. GLA is a novel therapeutic agent for controlling sepsis-related liver dysfunction.

AB0005 INTEGRATED ANALYSIS OF lncRNAs AND mRNAs EXPRESSION PROFILING IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by over-activity of lymphocytes, production of autoantibodies and effects on multiple organs 1. Growing evidences suggest long noncoding RNAs (lncRNAs) and mRNAs widely participate in physiological and pathological processes. However, knowledge of related lncRNAs and mRNAs in SLE remains limited.

Objectives

The aim of our study is to investigate the levels of differential expression of lncRNAs and mRNAs in the peripheral blood mononuclear cells (PBMCs) of SLE patients and their correlation with disease activity, clinical features and cell differentiation.

Methods

Peripheral venous blood 4ml were collected from 11 patients with SLE before and after treatment and 11 sex-and age-matched healthy individuals and saved in EDTA tubes. PBMCs were isolated from peripheral blood samples by Ficoll-Histopaque density gradient centrifugation. Total RNA was extracted from PBMCs with TRIzol reagent. RNAs amount and quality were quantified by using a NanoDrop ND-1000. Peripheral blood samples were sent to Novogene Co. Ltd (Beijing, China) for sequencing. The DESeq package in R language was used to analyze the differential expression of lncRNAs and mRNAs in the two groups. GO and KEGG databases analyze the potential biological functions and signal transduction and disease pathways affected by abnormal expression of lncRNAs and mRNAs2.

Results

According to the RNAs expression profiles, 338 lncRNAs (173 upregulated and 165 downregulated) and 2020 mRNAs (1292 upregulated and 728 downregulated) were differentially expressed between SLE patients and control groups. In addition, 17 lncRNAs were significantly downregulated and 66 mRNAs (47 upregulated and 19 downregulated) were differentially expressed between active and treated SLE patients. There were 1645 RNAs up-expression in active SLE patients and 36 RNAs under-expression in treated SLE patients, and total 14 RNAs changed direction of expression. GO and KEGG pathway analysis showed most of mRNAs were related to transcription, inflammation and immunity. The relativity between aberrantly expressed RNAs and clinical characteristics of active and treated SLE patients were shown in Table 1.

Conclusion

Dysregulation of lncRNAs and mRNAs involves in molecular regulation of SLE, which may support for diagnosis or determination of the susceptibility of individuals of SLE.

References

[1]Tsokos GC. Systemic lupus erythematosus. N Engl J Med 2011;365(22):2110-21. doi: 10.1056/NEJMra1100359 [published Online First: 2011/12/02]

[2]Zhang Y, Xu YZ, Sun N, et al. Long noncoding RNA expression profile in fibroblast-like synoviocytes from patients with rheumatoid arthritis. Arthritis Res Ther 2016;18(1):227. doi: 10.1186/s13075-016-1129-4 [published Online First: 2016/10/08]

Figure 1.

(A-C) Analysis of DElncRNAs and DEmRNAs of pre-treated SLE and cotrols. (A) The volcano plot with the DElncRNAs. (B) The volcano plot with the DEmRNAs. (C) The hierarchical clustering heatmap of DElncRNAs and DEmRNAs. (D-F) Analysis of DElncRNAs and DEmRNAs between pre-treated and treated SLE. (D) Volcano plot with the DElncRNAs. (E) Volcano plot with the DEmRNAs. (F) The hierarchical clustering heatmap of DElncRNAs and DEmRNAs. (G1-G5) Partial RNAs expression changed in active and treated SLE patients. Table 1 showed specific changed RNAs. (H1-H4) The top 20 GO and KEGG terms related to the up-regulated and down-regulated DEmRNAs. (I1-I3) GO and KEGG analyses of DEmRNAs between active and treated SLE patients.

Table 1:

The relativity between aberrantly expressed mRNA and LncRNA and clinical characteristics of active and treated SLE patients.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740) and the Natural Science Research Project of Shanxi Province (No.20210302123275).

Disclosure of Interests

None declared

Sodium MRI at 7T for Early Response Evaluation of Intracranial Tumors following Stereotactic Radiotherapy Using the CyberKnife

BACKGROUND AND PURPOSE

Conventionally, early treatment response to stereotactic radiotherapy in intracranial tumors is often determined by structural MR imaging. Tissue sodium concentration is altered by cellular integrity and energy status in cells. In this study, we aimed to investigate the feasibility of sodium MR imaging at 7T for the preliminary evaluation of radiotherapeutic efficacy for intracranial tumors.

MATERIALS AND METHODS

Data were collected from 16 patients (12 men and 4 women, 24-75 years of age) with 22 intracranial tumors who were treated with stereotactic radiation therapy using CyberKnife at our institution between December 1, 2016, and August 15, 2019. Sodium MR imaging was performed at 7T before and 48 hours, 1 week, and 1 month after CyberKnife radiation therapy. Tissue sodium concentration (TSC) was calculated and analyzed based on manually labeled regions of tumors.

RESULTS

Ultra-high-field sodium MR imaging clearly showed the intratumoral signal, which is significantly higher than that of normal tissue (t = 5.250, P <.001)., but the edema zone has some influence. The average TSC ratios of tumor to CSF in the 22 tumors, contralateral normal tissues, edema zones, frontal cortex, and frontal white matter were 0.66 (range, 0.23-1.5), 0.30 (range, 0.15-0.43), 0.58 (range, 0.25-1.21), 0.25 (range, 0.17-0.42), and 0.30 (range, 0.19-0.49), respectively. A total of 12 tumors in 8 patients were scanned at 48 hours, 1 week, and 1 month after treatment. The average TSC at 48 hours after treatment was 0.06 higher than that before treatment and began to decrease at 1 week. The TSC ratios of 10 continued to decline and 2 tumors increased at 1 month, respectively. Tumor volume decreased by 2.4%-99% after 3 months.

CONCLUSIONS

Changes in the TSC can be quantified by sodium MR imaging at 7T and used to detect radiobiologic alterations in intracranial tumors at early time points after CyberKnife radiation therapy.

[ ≥ ]

Objective: To investigate the safety and efficacy of retroperitoneal laparoscopic selective renal artery branch occlusion with nephron sparing surgery in patients with renal carcinoma of stage ≥ T1b. Methods: From July 2016 to September 2020, 35 patients with renal cancer ≥T1b underwent retroperitoneoscopic nephron sparing surgery in the First Affiliated Hospital of Shenzhen University. The surgical methods were retroperitoneoscopic nephron sparing surgery with total renal artery occlusion (group A) or selective renal artery branch occlusion (group B). Operation time, heat ischemia time, blood transfusion rate, positive margin rate, intraoperative blood loss, postoperative complications and length of hospital stay were compared between the two groups, and the total glomerular filtration rate (GFR) and the single-nephron glomerular filtration rate (sGFR) of the offected kidneys were compared between the two groups before, 3 months after and 12 months after surgery. Results: Among the 35 patients, 19 were male and 16 were female, aged (55.7±8.4) years and the body mass index is (24.6±3.1) kg/m². The tumor diameter was (54.7±10.3) mm. The difference was statistically significant of operative time between group A and B [(103.5±14.3) vs (123.2±14.1) min,P=0.003]. There were no significant differences in thermal ischemia time, blood transfusion rate, positive margin, intraoperative blood loss, incidence of postoperative complications and length of hospital stay between the two groups (all P>0.05). The decrease of renal sGFR in the group A was significantly higher than group B at 3 months and 12 months after surgery [(23.1±3.6) vs (29.1±7.1) ml/min;(25.9±4.7) vs (30.7±7.2),both P<0.05]. Conclusion: Retroperitoneal laparoscopic selective renal artery branch occlusion and neon-sparing surgery for patients with ≥ T1b stage renal carcinoma is a safe and effective surgical method, which can well protect the renal function of patients in the early postoperative stage without increasing intraoperative blood loss and postoperative complications.

COVID-19 prevention measures reduce dengue spread in Yunnan Province, China, but do not reduce established outbreak

The COVID-19 pandemic and measures against it provided a unique opportunity to understand the transmission of other infectious diseases and to evaluate the efficacy of COVID-19 prevention measures on them. Here we show a dengue epidemic in Yunnan, China, during the pandemic of COVID-19 was dramatically reduced compared to non-pandemic years and, importantly, spread was confined to only one city, Ruili. Three key features characterized this dengue outbreak: (i) the urban-to-suburban spread was efficiently blocked; (ii) the scale of epidemic in urban region was less affected; (iii) co-circulation of multiple strains was attenuated. These results suggested that countermeasures taken during COVID-19 pandemic are efficient to prevent dengue transmission between cities and from urban to suburban, as well to reduce the co-circulation of multiple serotypes or genotypes. Nevertheless, as revealed by the spatial analysis, once the dengue outbreak was established, its distribution was very stable and resistant to measures against COVID-19, implying the possibility to develop a precise prediction method.

Corrigendum: Characterization of SARS-CoV-2 Variants N501Y.V1 and N501Y.V2 Spike on Viral Infectivity

[This corrects the article DOI: 10.3389/fcimb.2021.720357.].

Characterization of SARS-CoV-2 Variants N501Y.V1 and N501Y.V2 Spike on Viral Infectivity

SARS-coronavirus 2 (SARS-CoV-2), pathogen of coronavirus disease 2019 (COVID-19), is constantly evolving to adapt to the host and evade antiviral immunity. The newly emerging variants N501Y.V1 (B.1.1.7) and N501Y.V2 (B.1.351), first reported in the United Kingdom and South Africa respectively, raised concerns due to the unusually rapid global spread. The mutations in spike (S) protein may contribute to the rapid spread of these variants. Here, with a vesicular stomatitis virus (VSV)-based pseudotype system, we demonstrated that the pseudovirus bearing N501Y.V2 S protein has higher infection efficiency than pseudovirus with wildtype (WT) and D614G S protein. Moreover, pseudovirus with N501Y.V1 or N501Y.V2 S protein has better thermal stability than WT and D614G, suggesting these mutations of variants may increase the stability of SARS-CoV-2 S protein and virion. However, the pseudovirus bearing N501Y.V1 or N501Y.V2 S protein has similar sensitivity to inhibitors of protease and endocytosis with WT and D614G. These findings could be of value in preventing the spread of virus and developing drugs for emerging SARS-CoV-2 variants.

Folic Acid Alleviates High Glucose and Fat-Induced Pyroptosis via Inhibition of the Hippo Signal Pathway on H9C2 Cells

Diabetic cardiomyopathy (DCM) is the leading cause of death in diabetic patients. Folic acid has a protective effect on diabetes-induced cardiomyocyte damage. The aim of this study was to explore the effects of folic acid on cardiomyocytes cultured under high glucose and fat (HGF) conditions and type 2 diabetes mellitus (T2DM) mice, and elucidate the underlying mechanisms. Bioinformatics analysis was used to identify the potential drugs through the Drug-Gene Interaction database. H9C2 cardiomyocytes were cultured with 30 mM glucose and 500 nM palmitic acid in the presence or absence of folic acid or YAP1 inhibitor (verteporfin) or YAP1 siRNA. The cell viability and lactate dehydrogenase (LDH) release were measured using specific assay kits. Pyroptosis was detected by flow cytometry. The concentrations of IL-1β and IL-18 in the supernatants were measured by ELISA. The NLRP3, ASC and caspase-1 mRNA levels were detected by qRT-PCR and that the proteins expression of NLRP3, ASC, cleaved caspase-1 (p10), caspase-1, YAP1, p-YAP1, LATS1 and P-LATS1 were detected by Western blotting. C57BL/6 mice were fed with high fat diet (HFD) combined with streptozotocin (STZ) intraperitoneally to establish a T2DM model, folic acid or PBS treatment for 8 weeks by oral gavage, blood glucose and body weight were measured every 4 weeks, mouse heart tissue was used to detect pyroptosis and hippo signaling pathway related protein expression. We identified 427 differentially expressed genes in the cardiac tissues of high fat diet + streptozotocin mice, among the 30 most significantly DEGs, folic acid was predicted to be the most likely therapeutic drug. Folic acid alleviated HGF-induced cell damage in vitro and in vivo by decreasing activation of the Hippo pathway, as indicated by lower LDH release and increased cell viability, and decreased expression of NLRP3, ASC, cleaved caspase-1, IL-1β, IL-18, p-YAP and p-LATS. Verteporfin or YAP1 siRNA neutralized the protective effect of folic acid by reversing YAP1-induced pyroptosis. Folic acid reduced NLRP3 inflammasome-mediated pyroptosis by down-regulating the Hippo signaling pathway, thereby effectively reducing T2DM-induced damage in H9C2 cells and animals.

POS0396 THE LEVEL OF PERIPHERAL REGULATORY T CELLS IS ASSOCIATED WITH THE CHANGES OF INTESTINAL MICROBIOTA IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) is a systemic autoimmunity inflammation disease characterized with chronic aggressive arthritis and the presence of abnormal antibodies. Several observations showed that the breakdown of immune tolerance caused by many complex interactions was involved in the development of RA[1]. However, the pathogenesis of RA remained unclear. It has been confirmed that the imbalance of Th17 and Treg cells play a crucial role in destroying immune tolerance [2]. Besides, researches showed that intestinal microbiota can influence host immunity by acting on the immune cells to play pro-inflammatory or anti-inflammatory effect, and in turn immune system can also regulate the microbiota[3, 4]. Thus, a frontier point of view in the field of rheumatism, immune microecology, was proposed, which is a novel concept for the breakdown of immune tolerance. Studies have confirmed that there was an imbalance of intestinal microbiota in patients with RA [4]. But the relationship between the CD4+T subsets cells and intestinal microbiota in RA is unknown.

Objectives:

We detected and compared the absolute number of CD4+T cells subsets in the peripheral blood and the proportion or abundance of intestinal microbiota in patients with RA and healthy adults, and then analyzed the relationship between them to explore the role of CD4+T cells subsets and intestinal microbiota in the pathogenesis of RA.

Methods:

We collected the sample of stool and blood from 15 patients with RA hospitalized at the Second Hospital of Shanxi Medical University and 8 age and gender-matched healthy controls(HC). The absolute number of CD4+T cells subsets including Th1, Th2, Th17 and Treg cells were detected by flow cytometry. The 16S rRNA in the stool specimens were sequenced by the Roche/45 high-throughput sequencing platform. We analyzed whether there was correlarion between CD4+T subsets cells and intestinal microbiota.

Results:

Patients with RA had a higher level of Christensenellaceae and a lower level of Pseudomonadaceae as compared with those of HCs at the family level (p<0.05). And at the genus level, the patients with RA had higher levels of Ruminococcus torques, Christensenellaceae R-7, Ruminiclostridium 9 and Ruminococcus 1 compared with those of HCs (p<0.05) (Figure 1).And the Ruminococcus torques at the genus level was negative correlated with the absolute number of Treg cells (p<0.001) (Figure 2).

Conclusion:

The results here suggested that there were different proportion or abundance of intestinal microbiota between the patients with RA andHCs. And the changes of intestinal microbiota such as Ruminococcus torques were associated with Treg cells, further indicating that the imbalance of intestinal microbiota in RA can destory the immune tolerance. The above results uncovered that the intestinal microbiota had immunomodulatory function, which may be the upstream mechanism participated in the pathogenesis of RA.

References:

[1]Weyand CM, Goronzy JJ. The immunology of rheumatoid arthritis. Nat Immunol 2021, 22(1): 10-18.

[2]Weyand CM, Goronzy JJ. Immunometabolism in the development of rheumatoid arthritis. Immunol Rev 2020, 294(1): 177-187.

[3]Brown EM, Kenny DJ, Xavier RJ. Gut Microbiota Regulation of T Cells During Inflammation and Autoimmunity. Annu Rev Immunol 2019, 37: 599-624.

[4]du Teil Espina M, Gabarrini G, Harmsen HJM, Westra J, van Winkelhoff AJ, van Dijl JM. Talk to your gut: the oral-gut microbiome axis and its immunomodulatory role in the etiology of rheumatoid arthritis. FEMS Microbiol Rev 2019, 43(1).

Figure 1.

At the family level (a-b) and the genus level(c-f), the relative abundance of intestinal microbiota in patients with RA and HCs were different. Data were expressed as median (Q1, Q3) and analyzed by Wilcoxon test. (*** P < 0.001, **P < 0.01 and *P < 0.05).

Figure 2.

A heatmap shows the correlation between the intestinal microbiota and CD4+T cells in patients with RA, and Ruminococcus torques at the genus level was negative related with Treg cells. (Colors indicate the Spearman rank correlation, *** P < 0.001).

Disclosure of Interests:

None declared

OP0307 GUT MICROBIOTA AND ITS RELEVANCE TO PERIPHERAL LYMPHOCYTE SUBPOPULATION IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is an autoimmune disease with disturbance of lymphocyte subpopulations1. Growing experimental and clinical evidence suggests that chronic inflammatory response induced by gut microbiome critically contribute to the development of SLE2 3.

Objectives:

To investigate the characteristics of gut microbiome and the associations between flora and peripheral lymphocyte subpopulations in SLE patients.

Methods:

A total of 19 SLE patients who fulfilled the 2019 American college of Rheumatology (ACR) and European League Against Rheumatism (EULAR) classification criteria and 16 age- and sex- matched healthy controls (HC) were enrolled in this study. The peripheral T lymphocyte subsets of these participants were assessed by flow cytometry and the gut microbiota were investigated via 16s rRNA. Indicators of disease activity such as erythrocyte sedimentation rate (ESR), complement C3 and C4 were recorded at the same time. Mann-Whitney U test was applied to compare T lymphocyte subsets between SLE patients and HC. Spearman analysis was used for calculating correlation between T subsets and highly expressed differential flora as well as their correlation with disease activity indicators. All P-values reported herein were two-tailed and P-value<0.05 was taken as statistically significant.

Results:

SLE patients had higher proportions of Th17 cells (P=0.020) and γδT cells (P=0.018) but lower levels of Treg cells (P=0.001), Tfh cells (P=0.018) and Naïve CD4+T cells (P=0.004) (Figure 1a-e). The diversity and relative abundance of intestinal flora in patients with SLE were significantly different from those in HCs. Detailly, the α-diversity was decreased in SLE (P<0.05) (Figure 2a-c). Compared with HC, 11 species of flora were discovered to be distinctly different(P<0.05) (Figure 2d-e). Moreover, there was a significant positive correlation between Treg levels and Ruminococcus2 (P=0.042), Th17 and Megamonas (P=0.009), γδT and Streptococcus (P=0.004) as well as Megamonas (P=0.003), Tfh and Bacteroides (P=0.040). Whereas Th1 levels and Bifidobacterium were negatively correlated in these participants (P=0.005). As for clinical disease measures, there were negative correlations not only between ESR and Treg cells (P=0.031) but also C4 and the amount of Unclassified Ruminococcaceae (P=0.032).

Conclusion:

Abnormality of T cell subsets, especially the level of Naïve CD4+T, γδT, Tfh, Treg, and Th17 cells contributes to the occurrence and progression of SLE, which may be related to the disturbance of gut microbiota. Therefore it is necessary to attach importance to the alteration of gut microbiota to prevent the outbreak of inflammation and maybe they can be identified as biomarkers predicting disease activity.

References:

[1]Katsuyama T, Tsokos GC, Moulton VR. Aberrant T Cell Signaling and Subsets in Systemic Lupus Erythematosus. Front Immunol 2018;9:1088. doi: 10.3389/fimmu.2018.01088 [published Online First: 2018/06/06]

[2]López P, de Paz B, Rodríguez-Carrio J, et al. Th17 responses and natural IgM antibodies are related to gut microbiota composition in systemic lupus erythematosus patients. Sci Rep 2016;6:24072. doi: 10.1038/srep24072 [published Online First: 2016/04/06]

[3]Esmaeili SA, Mahmoudi M, Momtazi AA, et al. Tolerogenic probiotics: potential immunoregulators in Systemic Lupus Erythematosus. J Cell Physiol 2017;232(8):1994-2007. doi: 10.1002/jcp.25748 [published Online First: 2016/12/21]

Acknowledgements:

This project was supported by National Science Foundation of China (82001740), Open Fund from the Key Laboratory of Cellular Physiology (Shanxi Medical University) (KLCP2019) and Innovation Plan for Postgraduate Education in Shanxi Province (2020BY078).

Disclosure of Interests:

None declared.

[Tobacco dependence status and influencing factors among smokers aged 40 or older in China]

Objective: To understanding tobacco dependence and its influencing factors among smokers aged 40 or older in China and provide scientific data for the implementation of smoking cessation intervention. Methods: The data of this study were collected from 125 surveillance sites in 31 provinces (autonomous regions and municipalities) of chronic obstructive pulmonary disease (COPD) surveillance in China (2014 and 2015). The relevant variables of smoking status and tobacco dependence among people aged 40 or older were collected by face-to-face interview. The weighted proportion of tobacco dependence and its 95%CI and influencing factors among current smokers and daily smokers aged 40 or older in China were estimated with complex sampling weights. Results: A total of 22 380 current smokers and 19 999 daily smokers were included in the analysis. The proportion of high tobacco dependence of current smokers aged 40 or older was 31.1% (29.3%-32.9%). The proportion of high tobacco dependence was higher in men than in women, and higher in rural smokers than urban smokers. The proportion was 33.3% (31.3%-35.2%) in 40 to 59 years old smokers, which was higher than older age group. The proportion of high tobacco dependence among daily smokers aged 40 or older was 35.0% (33.0%-37.0%), and was 35.8% (33.8%-37.8%) in men and 22.0% (16.8%-27.2%) in women. Among current smokers and daily smokers, with the decrease of education level, the proportion of high tobacco dependence increased. The proportion of high tobacco dependence of smokers who started smoking before 18 years old was significantly higher than those who started smoking after 18 years old. The ratio of high tobacco dependence of smokers with chronic respiratory symptoms was higher than that of asymptomatic smokers. There was no significant difference in the tobacco dependence between patients with chronic diseases or chronic respiratory diseases and non patients (P>0.05). Smokers with diabetes, cardiovascular and cerebrovascular diseases and hypertension had a slightly lower proportion of high tobacco dependence than smokers without above diseases (P<0.05). Multivariate logistic regression analysis showed that men, central and eastern regions, 40-59 age group, engaged in agriculture, forestry, animal husbandry, fishery industry, water conservancy, manufacture, transportation and commercial services occupation, low education level and smoking onset age less than 18 years old had a high risk of high tobacco dependence. Conclusions: The proportion of high tobacco dependence among current smokers aged 40 or older is high in China, so there is a huge demand for smoking cessation interventions. Effective measures should be taken to promote smoking cessation intervention in China.

DPP4 inhibition mitigates ANG II-mediated kidney immune activation and injury in male mice

Recent evidence suggests that dipeptidyl peptidase-4 (DPP4) inhibition with saxagliptin (Saxa) is renoprotective under comorbid conditions associated with activation of the renin-angiotensin-aldosterone system (RAAS), such as diabetes, obesity, and hypertension, which confer a high cardiovascular risk. Immune system activation is now recognized as a contributor to RAAS-mediated tissue injury, and, importantly, immunomodulatory effects of DPP4 have been reported. Accordingly, we examined the hypothesis that DPP4 inhibition with Saxa attenuates angiotensin II (ANG II)-induced kidney injury and albuminuria via attenuation of immune activation in the kidney. To this end, male mice were infused with either vehicle or ANG II (1,000 ng/kg/min, s.c.) for 3 wk and received either placebo or Saxa (10 mg/kg/day, p.o.) during the final 2 wk. ANG II infusion increased kidney, but not plasma, DPP4 activity in vivo as well as DPP4 activity in cultured proximal tubule cells. The latter was prevented by angiotensin receptor blockade with olmesartan. Further, ANG II induced hypertension and kidney injury characterized by mesangial expansion, mitochondrial damage, reduced brush border megalin expression, and albuminuria. Saxa inhibited DPP4 activity ∼50% in vivo and attenuated ANG II-mediated kidney injury, independent of blood pressure. Further mechanistic experiments revealed mitigation by Saxa of proinflammatory and profibrotic mediators activated by ANG II in the kidney, including CD8⁺ T cells, resident macrophages (CD11b^hiF4/80^loLy6C^-), and neutrophils. In addition, Saxa improved ANG II suppressed anti-inflammatory regulatory T cell and T helper 2 lymphocyte activity. Taken together, these results demonstrate, for the first time, blood pressure-independent involvement of renal DPP4 activation contributing to RAAS-dependent kidney injury and immune activation.NEW & NOTEWORTHY This work highlights the role of dipeptidyl peptidase-4 (DPP4) in promoting ANG II-mediated kidney inflammation and injury. Specifically, ANG II infusion in mice led to increases in blood pressure and kidney DPP4 activity, which then led to activation of CD8⁺ T cells, Ly6C^- macrophages, and neutrophils and suppression of anti-inflammatory T helper 2 lymphocytes and regulatory T cells. Collectively, this led to kidney injury, characterized by mesangial expansion, mitochondrial damage, and albuminuria, which were mitigated by DPP4 inhibition independent of blood pressure reduction.

Cholinergic receptors play a role in the cardioprotective effects of anesthetic preconditioning: Roles of nitric oxide and the CaMKKβ/AMPK pathway

Vagus nerve activation may have important therapeutic significance for myocardial ischemia-reperfusion (IR) injury. Nitric oxide (NO) plays a vital role in the cardioprotective effects of anesthetic preconditioning (APC). Moreover, acetylcholine (ACh) prevents cardiomyocyte damage by activating AMP-activated protein kinase (AMPK) and increasing the phosphorylation of Ca²⁺/calmodulin-dependent protein kinase β (CaMKKβ). The aim of the present study was to determine whether APC could protect heart function by antagonizing IR damage via the cholinergic system. It was hypothesized that the NO synthase (NOS)/CaMKKβ/AMPK pathway might be involved in the cardioprotective effects induced by cholinergic receptor activation. Isolated rat hearts were subjected to ischemia for 30 min followed by 120 min of reperfusion. Volatile anesthetic sevoflurane (3.5%) was administered for 15 min before ischemia, then rinsed for 15 min. The muscarinic acetylcholine receptor (mAChR) antagonist atropine (ATR; 100 nM) and the nicotinic acetylcholine receptor (nAChR) antagonist hexamethonium (HEM; 50 µM) were administered 10 min before APC. Both mAChR and nAChR were involved in APC-induced cardioprotection. ATR and HEM treatment both abolished the protective effects of APC on IR damage in isolated hearts, demonstrating the importance of cholinergic receptors in the protection mechanism of APC. The present study thus suggests that APC plays a cardioprotective role, in part, by regulating neurohumoral pathways. In addition, there may be functional coupling between the two cholinergic receptors, and the NOS and CaMKKβ/AMPK pathways may play roles in shared pathways that mediate the cardioprotective effects of APC. These findings may provide insight into potential new mechanisms of APC-induced cardioprotection against IR injury.

Abstract P024: Proximal Tubule Specific Dpp4 Deletion Slows Kidney Disease Progression In Western Diet-fed Obese Mice

Background: Obesity is a major risk factor for Chronic Kidney Disease progression to End Stage Renal Disease and/or Dialysis. Increased absorption of fats and/or sugars from Western Diet (WD), likely leads to kidney tubular injury in obesity. We observed that global dipeptidyl peptidase 4 (DPP4) deletion as well as use of inhibitors in WD-fed mice results in decreased kidney injury which, in turn was associated with a decrease in proximal tubule DPP4. Therefore, we hypothesized that proximal tubule (PT) DPP4 activation leads to injury and progression of kidney disease.

Methods: PT DPP4-KO and WT littermates were fed a WD starting 4-6 wks of age and continued for 2 years. FITC-sinestrin-based GFR and albuminuria were monitored periodically. Tissue histology was performed at select intervals. GeLC-MS was used to separate kidney peptides and Scaffold 4/iPathwayguide used to analyze the Proteomics data.

Results: WD-fed WT mice gained 150-200% weight of chow-fed [CD] mice and had a greater decline in GFR than CD-fed animals over 2 years (50% vs. 20%, p<0.05). WD-fed PT-DPP4-KO mice had a lesser decline (~35%) when compared to WT mice. This was true for both male and female mice. Concomitantly, there was an increase in albuminuria in WD-fed WT mice that was mitigated in PT-DPP4-KO mice. PAS/PSR stained sections showed worsening fibrosis, tubular dilatation and glomerulomegaly, tubular vacuolization in WD-fed WT mice that was mitigated in PT-DPP4-KO mice. Oil Red O staining showed increased fat accumulation in glomeruli and tubules of WD-fed WT mice that was mitigated in KO mice. Proteomics analysis followed by immunoblots showed that WD-feeding led to an increase in cell adhesion proteins and ribosomal machinery that was significantly suppressed by KO. In addition, there was a shift towards reduction in gluconeogenesis and improved fatty acid oxidation in KO mice.

Conclusion: Obesity without diabetes can lead to chronic decline in GFR in both male and female mice. DPP4 inhibition may slow the decline if started early in the course of developing obesity and/or metabolic syndrome.

[Spatio-temporal clustering of hepatitis A in Gansu provice, 2004-2018]

Objective: To understand the characteristics of spatiotemporal clustering on hepatitis A in Gansu province and to provide evidence for hepatitis A prevention and control. Methods: Data related to hepatitis A were retrieved from National Notifiable Disease Report System, ArcGIS 10.3 and SaTScan 9.1 in Gansu province from 2004 to 2018. Results: The annual average report incidence rate of hepatitis A was 10.91/100 000, showing a descending trend with no periodic or seasonal features. After the implementation of national expanded immunization program, high annual incidence rates had been seen in Linxia Hui autonomous prefecture and Gannan Tibetan autonomous prefecture. From 2004 to 2012, the lowest RR value appeared in the 0-9 age group (P=0.000) while the highest RR value was in the over 60 age group during 2013-2018 except for the age 0-9 group in 2015. The annual average incidence rate was increasing from south to north and west to east, across the territory. Results from the temporal scanning program revealed that the incidence of hepatitis A was temporally aggregated from 2004 to 2018. For spatio-temporal scanning of 2004-2008, data showed one most likely cluster area (radius: 91.95 km, Time frame: 2004-2005), apparel mainly in Linxia and Longnan cities. Results from the spatio-temporal scanning program of 2009-2018 also showed that the most likely cluster areas (radius: 183.26 km, Time frame: 2009-2012) were in Gannan, Linxia, Dingxi and Longnan areas. Conclusions: The reported incidence rates of hepatitis A were declining, without significant periodic or seasonal pattern in Gansu province from 2004 to 2018. In the 0-9 years-old group, the incidence rate showed the lowest, while the highest was in the 60 year-olds group. Spatio-temporal clustering of hepatitis A was observed in Gansu province from 2004 to 2018. Strategies on prevention and control of the disease should be targeted in the southwest regions of the province.

A preoperative whey protein and glucose drink before hip fracture surgery in the aged improves symptomatic and metabolic recovery

BACKGROUND AND OBJECTIVES

We investigated the effects of a carbohydrate-whey protein solution on aged patients undergoing hip fracture surgery.

METHODS AND STUDY DESIGN

Forty patients were randomly assigned to the carbohydrate-whey protein (CHP) group or the control group (CTL). In the CHP group, a mixed solution of CHP was orally administered to patients before surgery: 400 mL was administered on the day before surgery, and 200 mL was administered 3 h before surgery. The size of the liquid dark area in the gastric antrum was measured by ultrasound, and the bleeding volume during surgery was assayed. The incidence of nausea, vomiting, thirst, hunger, and days of hospitalization and the levels of blood glucose, C-reactive protein (CRP) and serum albumin were assessed.

RESULTS

There was no obvious liquid dark space in the gastric antrum. CHP administration improved postoperative thirst and hunger and resulted in increased albumin levels and decreased CRP concentrations and blood glucose fluctuations.

CONCLUSIONS

Oral CHP before hip fracture surgery reduces the incidence of postoperative thirst and hunger and improves recovery in the aged.

SAT0278 LOW-DOSE IL-2 RESTORES TREG-MEDIATED IMMUNE TOLERANCE IN PATIENTS WITH ANCA-ASSOCIATED VASCULITIS

Background:

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of autoimmune disease that can cause systemic organ damage, including granulomatosis with polyangiitis(GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis(EGPA)[1]. Several observations have showed that the breakdown of immune tolerance was involved in the pathogenesis of AAV [2], furthermore, a single, open and clinical trial demonstrates that IL-2 can be used to treat patients with GPA [3]. But there is still a lack of understanding of the relationship between Th17 / Treg and AAV and evidence for the therapeutic effect of IL-2 on AAV, which needs further exploration.

Objectives:

We first measured the absolute number of CD4+T subsets in peripheral blood of patients to explore the pathogenesis of AAV, and then investigated the effects of short-term and low-dose recombinant human IL-2 (rhIL-2) on CD4+T subsets of patients to analyze the regulatory effect of IL-2 on AAV.

Methods:

49 patients with AAV, hospitalized at the Second Hospital of Shanxi Medical University from the May 2016 to the November 2019 were enrolled, including 36 patients who were only received conventional glucocorticoids and DMARDs, and other 13 patients who were not only received these treatments but were also injected subcutaneously rhIL-2(50WIU/day for a 5-day course). 31 age and gender-matched healthy adults were selected as controls. The absolute number of Th17 and Treg cells in peripheral blood of health controls and the patients before and after treatment was detected by flow cytometry.

Results:

There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls (P<0.001) leading to a higher Th17/Treg ratio in the patients with AAV, but there was no statistically significant in the absolute number of Th17 cells between the patients and healthy controls. After the treatment of short-term and low-dose IL-2, there was a significant increase in the absolute number of Treg cells (P<0.01) leading to a decrease in the ratio of Th17 and Treg (p<0.05).The absolute number of Th17 had a trend towards higher values but was not statistical significance.

Conclusion:

The difference of Treg cells between the patients and healthy controls suggested that the decreased number of Treg cells failed to control autoimmune inflammatory response contributing to the pathogenesis of AAV. After the treatment of short-term and low-dose rhIL-2, there was a more significant increase in the absolute number of Treg cells showing that IL-2 could selectively stimulate the growth of Treg cells and restore the Treg-mediated immune tolerance in patients with AAV to achieve disease remission.

References:

[1]Cosmi, L.,Th17 and Treg lymphocytes as cellular biomarkers of disease activity in Granulomatosis with Polyangiitis.Eur J Immunol, 2017.47(4): p. 633-636.

[2]Pagnoux, C.,Updates in ANCA-associated vasculitis.Eur J Rheumatol, 2016.3: p. 122-133.

[3]Rosenzwajg, M., et al.,Immunological and clinical effects of low-dose interleukin-2 across 11 autoimmune diseases in a single, open clinical trial.Annals of the Rheumatic Diseases, 2019.78(2): p. 209-217.

Disclosure of Interests:

None declared

THU0325 REDUCED OF TREG CELLS ASSOCIATED WITH THE DISEASE ACTIVITY OF ANCA-ASSOCIATED VASCULITIS

Background:

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of autoimmune disease that can cause systemic organ damage, characterized with the presence of abnormal antibodies (ANCAs) in the circulation and the small- and medium-vessel vasculitis[1].However,the etiology of AAV remained unclear. Several observations have showed that the breakdown of immune tolerance caused by many complex interactions was involved in the pathogenesis of AAV[2].It has been confirmed that the disorder of the CD4+T cell,especially the imbalance of Th17 and Treg cells can destroy the immune tolerance and cause many autoimmune disease[3]. But the relationship between the Th17/Treg and AAV is unknown.

Objectives:

We investigated the absolute numbers of CD4+T subsets cells in peripheral blood of patients with AAV and healthy adults,and then compared them in different disease activity of AAV to explore the role of CD4+T subsets cells in the pathogenesis and development of AAV.

Methods:

49 patients with AAV,hospitalized at the Second Hospital of Shanxi Medical University from the May 2016 to the November 2019 were enrolled, and 31 age and gender-matched healthy adults were anticipated as controls.According to BVAS, the patients were divided into disease-activity group (BVAS≥15, n=27) and non-disease-activity group (BVAS<15, n=22). The absolute numbers of CD4+T subsets cells including Th17 and Tregs in peripheral blood of these individuals were detected by flow cytometry.We analyzed whether there was difference of CD4+T subsets between the patients and healthy controls,and between disease-activity group and non-disease-activity group.

Results:

There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls,especially in the disease-activity group. The absolute numbers of Treg cells was decreased in the patients with AAV compared with healthy controls (P<0.001) leading to a higher Th17/Treg ratio in the patients (P<0.01).Similarly,the absolute number of Treg cells was decreased in the disease- activity group (P<0.01) compared with the non-disease-activity group, and the absolute number of Treg cells was significant negative correlation with the disease activity indexes such as BVAS (r=-0.342,P=0.016), erythrocyte sedimentation rate(ESR) (r=-0.315,P=0.027) and C-reactive protein(CRP) (r=-0.305,P=0.033). But there was no statistically significant in the absolute number of Th17 cells between the patients and healthy controls, and between disease-activity group and non-disease-activity group.

Conclusion:

The results we investigated here suggested that the decreased number of Treg cells failed to control autoimmune inflammatory response and maintain immune tolerance, and the disease activity of AAV was associated with the reduced number of Treg cells.

Figure 1.

(A-C) Characteristics of the absolute number of Th17 cells and Treg cells in peripheral blood of healthy controls (n=31) and the patients with AAV (n=49). There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls leading to a higher Th17/Treg ratio in the patients with AAV. (D-F) The absolute number of Treg cells was decreased in the disease- activity group (n=27) compared with the non-disease-activity group (n=21). The absolute number of Th17 cells and Treg cells was detected by flow cytometry. Statistical analyses were performed by the Mann-Whitney U test. *p<0.05,**p<0.01, ***p<0.001.

References:

[1]Cosmi, L., Th17 and Treg lymphocytes as cellular biomarkers of disease activity in Granulomatosis with Polyangiitis. Eur J Immunol, 2017.47(4): p. 633-636.

[2]Pagnoux, C.,Updates in ANCA-associated vasculitis.Eur J Rheumatol, 2016.3: p. 122-133.

[3]Diller, M.L., et al., Balancing Inflammation: The Link between Th17 and Regulatory T Cells. Mediators Inflamm, 2016.2016: p. 6309219.

Disclosure of Interests:

None declared

Post-traumatic maxillofacial reconstruction with vascularized flaps and digital techniques: 10-year experience

The aim of this study was to present a treatment protocol for the individual repair of post-traumatic maxillofacial bone defects with vascularized flaps assisted by digital techniques. This study reviewed 20 patients with post-traumatic maxillofacial bone defects who underwent reconstruction with composite vascularized bone flaps assisted by digital techniques between April 2009 and July 2019. Preoperative computed tomography (CT) data were imported into ProPlan CMF software to complete virtual fracture reduction and reconstruction. Surgical navigation, three-dimensionally (3D) printed surgical plates, and prefabricated titanium mesh/plates were used to guide the actual surgery. All patients underwent open reduction and internal fixation and reconstruction surgery in one stage. CT data obtained at 1 week postoperative were imported into Geomagic Control software to evaluate the accuracy of the virtual surgical plan. The mean follow-up interval was 24 months (range 6-96 months). Donor and recipient site morbidity and second-stage procedures to rehabilitate the dentition and cosmetic organs were recorded. The flap success rate was 100%. Nine patients had deep circumflex iliac artery flaps and eleven patients had fibula flaps. The accuracy of computer-assisted surgery was 4.4±0.8mm. There were no postoperative complications. This study is novel in presenting a treatment protocol for individual computer-assisted reconstruction for post-traumatic maxillofacial bone defects with vascularized flaps.

NOS cofactor tetrahydrobiopterin contributes to anesthetic preconditioning induced myocardial protection in the isolated ex vivo rat heart

Anesthetic preconditioning (APC) may decrease the myocardium injury nearly 50% following ischemia/reperfusion (I/R) by enhancing recovery of cardiac function, reducing myocardial enzyme release and lowering infarct size when utilized as pretreatment or posttreatment agents. I/R increases nitric oxide (NO) production through endothelial NO synthase (NOS3) and heat shock protein 90 (HSP90). The present study aimed to observe the role of BH4 availability and the association of HSP90 with NOS3 in APC‑mediated cardioprotection against I/R injury. Isolated rat hearts were subjected to no‑flow ischemia for 30 min and reperfusion for 120 min. Sevoflurane (3.5%) was administered for 15 min followed by a 15 min washout prior to ischemia. 2,4-Diamino-6-hydroxypyrimidine (DAHP) or sepiapterin (SP) was administered for 40 min until the onset of ischemia. The results revealed that compared with pre‑ischemic basal levels, BH4 levels decreased and BH2 levels increased following I/R. BH4 levels were significantly increased and BH2 levels were significantly decreased in the APC + I/R hearts compared with the I/R group hearts. The BH4:BH2 ratio in the APC‑treated hearts was also increased compared with that in the I/R group hearts. SP increased the recovery of contractile function and the production of NO, and decreased the production of superoxide anion (O2·‑) in I/R heart, but did not elicit these effects in APC‑treated hearts. DAHP treatment inhibited the APC‑mediated recovery of contractile function, increased O2·‑ levels and decreased NO production, but had no effect in I/R hearts. The cardioprotection of APC was demonstrated to be modulated by the BH4 precursor SP, which increased BH4 levels, or DAHP, which inhibited GTP cyclohydrolase I. Both APC and SP treatments increased the combination of HSP90 and NOS3, which improved the NOS3 activity and function. The results suggested that BH4, which servesas a cofactor for NOS, mediated the resistance of APC to I/R injury by promoting the binding of HSP90 and NOS3.

[Diagnostic value of optical imaging combined with indocyanine green-guided sentinel lymph node biopsy in gastric cancer: a meta-analysis]

Objective: To systematically evaluate the diagnostic value of optical imaging combined with indocyanine green (ICG)-guided sentinel lymph node (SLN) biopsy in gastric cancer, and to identify potential factors that would influence diagnostic accuracy. Methods: Study was carried out by searching the electronic database of PubMed, Embase, Medline, Web of Science, and the Cochrane Library with keywords as "gastric/stomach" and "cancer/carcinoma/tumor/tumour/adenocarcinoma/neoplasm" and "sentinel lymph node" and "near-infrared/NIR or fluorescent imaging" and "indocyanine green/ICG" . Literature inclusion criteria: (1) gastric cancer clinical stage was cT0-3; (2) clinical stage determined by at least 2 kinds of imaging modalities; (3) optical imaging (near-infrared or fluorescence imaging) combined with ICG-guided SLN biopsy; (4) prospective study to predict lymph node metastasis; (5) intraoperative or postoperative pathology for all lymph nodes removed; (6) patients number in the literature >10 cases. Exclusion criteria: (1) patients with a history of ICG allergy or chemoradiotherapy; (2) previous history of endoscopic mucosal resection or endoscopic submucosal dissection; (3) patients with a variety of gastrointestinal tumor; (4) case reports, conference abstracts, clinical guidelines, editorials, reviews, meta-analysis and correspondence letters; (5) in vitro or animal experiments; (6) insufficient diagnostic efficacy data. The meta-analysis was performed in the Stata12.0 software using the "bivariate mixed-effects model" combined with the "midas" command to pool the data. Information such as true positive value, false positive value, false negative value, and true negative value of each included articles were extracted. The literature quality assessment map was drawn to describe the overall quality of the articles; the heterogeneity analysis was performed with the forest map, with P<0.01 considered as statistical significance; the funnel plot was used to describe publication bias, with P<0.1 considered as statistically significant. Area under curve (AUC) of summary receiver operator characteristic (SROC) was used to describe the diagnostic accuracy and the AUC closer to 1 indicated higher diagnostic accuracy. If there was heterogeneity (I(2)>50%) among studies, regression analysis and subgroup analysis were performed. P<0.05 was considered as statistically significant. Results: A total of 15 studies (1020 patients) were included. The optical imaging contained near-infrared (NIR) and fluorescent imaging (FI). The diagnostic value of optical imaging combined with ICG-guided SLN biopsy in gastric cancer was as follows: the pooled sensitivity (Sen) was 0.95 (95% CI: 0.82 to 0.99), specificity (Spe) was 1.00 (95% CI: 0.92 to 1.00), positive likelihood ratio (PLR) was 30.39 (95% CI: 9.14 to 101.06), negative likelihood ratio (NLR) was 0.05 (95% CI:0.01 to 0.20), diagnostic odds ratio (DOR) was 225.54 (95% CI: 88.81 to 572.77), AUC was 1.00 (95% CI: 0.99 to 1.00), threshold value was sensitivity=0.95 (95% CI: 0.82 to 0.99) and specificity=1.00 (95% CI: 0.92 to 1.00). Deeks method revealed DOR funnel plot of SLN biopsy was not asymmetrical obviously with significant difference (P=0.01), which indicated remarkable publishing bias. Meta-subgroup analysis showed that compared to FI, NIR imaging had higher sensitivity (0.98 vs. 0.73); compared to 0 minutes, optical imaging performed 20 minutes after ICG injection had higher sensitivity (0.98 vs. 0.70); compared to mean detected number of SLN of 4, mean detected number≥4 had higher sensitivity (0.96 vs. 0.68); compared to HE stain, immunohistochemistry + HE had higher sensitivity (0.99 vs. 0.84); compared to subserous injection of ICG, submucosa injection of ICG had higher sensitivity (0.98 vs. 0.40); compared to injection of 5 g/L ICG, 0.5 g/L and 0.05 g/L had higher sensitivity (0.98 vs. 0.83); compared to cT2-3 tumor, early stage (cT1) tumor had higher sensitivity (0.96 vs. 0.72); compared to ≤ enrolled 26 cases in the study, > 26 cases had higher sensitivity (0.96 vs. 0.65); compared to papers before 2010, papers after 2010 had higher sensitivity (0.97 vs. 0.81); whose differences were all significant. Sensitivity differences between mean tumor diameter of ≤30 cm and >30 cm, open surgery and laparoscopic surgery, lymph node regional dissection and retrieved dissection were not significant (all P>0.05). Conclusions: Optical imaging combined with ICG-guided SLN biopsy is clinically feasible, and especially suitable for early gastric cancer. However, the ICG being used in current studies may be overdosed. Higher sensitivity may be achieved from NIR imaging when compared with FI method.

Impact of genomic alterations on lapatinib treatment outcome and cell-free genomic landscape during HER2 therapy in HER2+ gastric cancer patients

Background

To identify predictive markers for responders in lapatinib-treated patients and to demonstrate molecular changes during lapatinib treatment via cell-free genomics.

Patients and methods

We prospectively evaluated the efficacy of combining lapatinib with capecitabine and oxaliplatin as first line neoadjuvant therapy in patients with previously untreated, HER2-overexpressing advanced gastric cancer. A parallel biomarker study was conducted by simultaneously performing immunohistochemistry and next-generation sequencing (NGS) with tumor and blood samples.

Results

Complete response was confirmed in 7/32 patients (21.8%), 2 of whom received radical surgery with pathologic-confirmed complete response. Fifteen partial responses (46.8%) were observed, resulting in a 68.6% overall response rate. NGS of the 16 tumor specimens demonstrated that the most common co-occurring copy number alteration was CCNE1 amplification, which was present in 40% of HER2+ tumors. The relationship between CCNE1 amplification and lack of response to HER2-targeted therapy trended toward statistical significance (66.7% of non-responders versus 22.2% of responders harbored CCNE1 amplification; P = 0.08). Patients with high level ERBB2 amplification by NGS were more likely to respond to therapy, compared with patients with low level ERBB2 amplification (P = 0.02). Analysis of cfDNA showed that detectable ERBB2 copy number amplification in plasma was predictive to the response (100%, response rate) and changes in plasma-detected genomic alterations were associated with lapatinib sensitivity and/or resistance. The follow-up cfDNA genomics at disease progression demonstrated that there are emergences of other genomic aberrations such as MYC, EGFR, FGFR2 and MET amplifications.

Conclusions

The present study showed that HER2+ GC patients respond differently according to concomitant genomic aberrations beyond ERBB2, high ERBB2 amplification by NGS or cfDNA can be a positive predictor for patient selection, and tumor genomic alterations change significantly during targeted agent therapy.

Cardioprotective effects of triiodothyronine supplementation against ischemia reperfusion injury by preserving calcium cycling proteins in isolated rat hearts

Hypothyroidism is associated with profound left ventricular dysfunction. Triiodothyronine (T₃) supplementation may improve cardiac function after ischemic reperfusion (I/R) injury. In the present study, the effect of T₃ on major calcium cycling proteins and high-energy phosphate content during I/R was evaluated. Isolated perfused rat hearts were divided into 5 groups: Sham Control (Sham, n=10), Control (n=8), T₃ 10 nM (T₃-10, n=10), T₃ 25 nM (T₃-25, n=10) and T₃ 50 nM (T₃-50, n=10). T₃ was administrated for 60 min before 30 min of ischemia and 120 min of reperfusion. The protein contents of Ca²⁺-release channels (RyR2), Ca²⁺-adenosine triphosphatase (SERCA2a), phospholamban (PLB), sarcolemmal Ca²⁺-adenosine triphosphatase (PMCA) and sodium-calcium exchanger (NCX), as well as the high-energy phosphate content in heart tissues were measured by western blot analysis. The results revealed that T₃ improved the contractile recovery (left ventricular developed pressure; +dP/dt, -dP/dt) after I/R. Western blotting assays demonstrated that I/R depressed the contents of RYR2, SERCA2a and phosphorylated RYR2 and PLB; there were no effects on the contents of PLB, PMCA and NCX. T₃ reversed I/R-induced degradation of RyR2 and SERCA2a, restored the phosphorylation of RyR2 and PLB, and preserved the high-energy phosphate contents of ATP and creatine phosphate. T₃ supplementation protected the heart against I/R injury via the preservation of Ca²⁺-cycling proteins and high-energy phosphate content.

Effects of isoflurane on complex II‑associated mitochondrial respiration and reactive oxygen species production: Roles of nitric oxide and mitochondrial KATP channels

Volatile anesthetics may protect the heart against ischemia‑reperfusion injury via the direct action on mitochondrial complexes and by regulating the production of reactive oxygen species (ROS). Recently, we reported that isoflurane induced the attenuation of mitochondrial respiration caused by complex I substrates. This process was not associated with endogenous production of mitochondrial nitric oxide (NO). In the present study, we investigated the effects of isoflurane on mitochondrial respiration and ROS production using complex II substrates. The detailed mechanism of these effects was explored with regards to NO production and the expression of mitochondrial ATP‑dependent K+ (mKATP) channels. Mitochondria were isolated from the heart of Sprague‑Dawley rats. The respiratory rates of mitochondria (0.5 mg/ml) were measured via polarography at 28˚C with computer‑controlled Clark‑type O2 electrodes. The complex II substrate succinate (5 mM) was used; 0.25 mM of isoflurane was administered prior to ADP‑initiated state 3 respiration. The mitochondrial membrane potential (ΔΨm) was measured under treatment with the substrate succinate, or succinate in the presence of the complex I inhibitor rotenone. The detection was achieved in a cuvette‑based spectrophotometer operating at wavelengths of 503 nm (excitation) 527 nm (emission) in the presence of 50 nM of the fluorescent dye rhodamine 123. The H2O2 release rates in the mitochondria were measured spectrophotometrically with succinate, or succinate and rotenone using the fluorescent dye Amplex red (12.5‑25 µM). The results indicated that isoflurane increased the state 3 and 4 respiration rates caused by succinate, which were higher than those noted in the control group in the presence of succinate alone. The NOS inhibitor L‑NIO or the NO‑sensitive guanylyl cyclase 1H‑[1,2,4]oxadiazolo[4,3‑a]quinoxalin‑1‑one did not inhibit the increase in the respiration rate (state 3) induced by isoflurane. The ROS scavengers SPBN and manganese (III) tetrakis (4‑benzoic acid) porphyrin chloride inhibited the increase in the respiration rate (state 3 and 4) induced by isoflurane. This effect was not noted for the putative KATP channel blockers 5‑hydroxydecanoic acid and glibenclamide. Isoflurane caused a greater decrease in the concentration of H2O2 during ADP‑initiated state 3 respiration, and L‑N5‑(1‑Iminoethyl)‑ornithine did not inhibit this effect. In conclusion, isoflurane was determined to modulate mitochondrial respiration and ROS production caused by the complex II substrate succinate. These effects were independent of endogenous mitochondrial NO generation and mitochondrial KATP channel opening.